Recently, computerization of vehicles has been progressing, various vehicle equipments, driving systems, auxiliary systems for the same, etc. are equipped with a number of electronic equipments, and the control of the electronic equipment is performed. Further, in a control apparatus for controlling such an on-vehicle electronic equipment, in order to realize a safe operation of the vehicle and improve the convenience and comfortability of vehicle occupants, a high safety and a reliability are required.
Therefore, in the control apparatus described above, in order to improve the safety and the reliability, even in the case that abnormality occurs in the control program of the electronic equipment, for example, provide a watchdog timer (WDT) and repeat start-up and reset of the WDT at every predetermined time so that the abnormal execution state of the control program does not continue over a certain time.
Further, for example, in the case that the above electronic equipment is an electric power steering apparatus, as described in Patent Document 1 (Japanese Published Unexamined Patent Application No. 2009-113618 A), a technology that accurately detects the abnormal execution state of the control program being undetectable by the WDT described above by measuring termination time of each task in a control section and performing detection of the abnormal execution state of the control program based on measured termination time of each task, is disclosed.
Moreover, in Patent Document 2 (Japanese Published Unexamined Patent Application No. 2006-90356 A), a technology that suppresses the occurrence of faults such as task missing and so on by detecting a task with a high processing load in a control apparatus for vehicle control and replacing with processing contents with a lower processing load based on a predetermined task congestion criterion, is disclosed.